FLORHAM PARK, N.J. -- When he was a kid in East Texas dreaming of becoming the next Emmitt Smith, Chris Ivory made loud touchdowns. His mother, a member of the Longview Police Department, turned on the siren in her cruiser whenever Chris scored in a pee wee game. Word of the running back's exploits traveled to the surrounding neighborhood at the speed of sound.

Now, some 15 years later, Ivory is having the same effect for the New York Jets. He's off to the best start of his career, creating so much noise across the NFL that people are finally starting to take notice:

Who is this guy? How did he remain a secret for so long? Can he maintain his 115-yard-per-game pace?

This has been a 10-year journey for Ivory, with most of it spent in the shadows. He grew up in Texas, but he never was a lone star. He was the overlooked recruit, the kid who teased with his natural ability but was never able to finish what he started -- not in his two college stops or his first NFL stop with the New Orleans Saints.

It's ironic because that's his greatest strength as a player -- the way he finishes runs. He does it with competitive greed and violence. More than 50 percent of his yardage -- 233 out of 460 -- has come after initial contact, one of the best ratios in the league. Everybody knows what he is, yet there's still a mystique about him.

"That's the thing: This guy is an unknown," said Marcel Shipp, the Jets' running backs coach. "You don't know what his potential is. I don't think there's a ceiling."

Chris Ivory, at 6 feet tall and 222 pounds, can run over opponents or around them. Brad Penner/USA TODAY Sports

Ivory, 27, always has been a hard guy to figure out, dating to his days at Longview High School. He was a punishing fullback in coach John King's triple-option offense, yet he didn't attract much interest from recruiters. Ivory played on a team that sent eight players to Division I schools, including Trent Williams, a Pro Bowl tackle for the Washington Redskins. Ivory wasn't even the most coveted player in the backfield; the big star was tailback Vondrell McGee, who went to Texas.

Ivory flashed tantalizing talent during his three years at Washington State, but he battled injuries at every turn and never carried the ball more than 60 times in a season. In July 2009, he was arrested and charged with assaulting another student, allegedly hitting him on the head with a bottle.

Ivory was indicted nearly a year later on a charge of second-degree assault -- a Class B felony. At the time, he denied any involvement; he refuses to talk about it anymore. He never did jail time, and the case was dismissed in 2011.

When it came time for the NFL, he was branded a character risk by scouts, but they didn't know the whole story.

Early in his college career, Ivory's mother, Judy Ivory-Gilliland, was stricken with viral meningitis and nearly died. She lapsed into a coma and spent two months in the hospital, and another four months recovering. Relatives suspect she got sick as a result of driving sick kids home from school in her police car, something she did to help out. She's that kind of person.

Distraught after learning of his mom's condition, Ivory flew home and spent all night in the hospital, praying at her bedside. The woman who made him smile with her siren was attached to a ventilator in a painfully silent room -- and he wanted to scream. People close to the introverted running back say it hit him hard.

"He got lost," King said. "He did some uncharacteristic things, but he got himself straightened out."

In a funk, Ivory returned to school, but it was difficult for him to be so far away from his mother. At times, he appeared distracted, according to former coaches. They put up with it because they saw fleeting moments of jaw-dropping talent, including 100-yard games against Stanford and Washington. Eventually, the patience ran out. A month after the alleged bottle incident, he was dismissed from the team for violating team rules: He overslept and missed a meeting. There was a new coaching staff at Washington State, and it wasn't interested in waiting for Ivory to fulfill his potential.

Ivory's best game for Washington State was a 114-yard rushing day against rival Washington in 2007. Jesse Beals / Icon Sportswire

One month before the 2009 season, Ivory was looking for a place to play. A former Washington State assistant, Dave Walkosky, was the head coach at Tiffin University, a Division II school in Ohio. He offered a spot to Ivory, who had never heard of the place.

"When I heard what happened, I was like, 'Are you kidding me? I've got a chance to get Chris Ivory? Am I missing something?'" Walkosky recalled.

Tiffin was a bad team, to put it kindly, and went 0-11 that season, including a 62-0 loss to Northern Michigan. After two games, Ivory walked into Walkosky's office and wanted to talk.

"We couldn't block anybody, and he was getting his butt kicked at tailback," Walkosky said. "I expected him to tell me, 'I can't do this, I'm leaving.' I wouldn't have blamed him. But he said, 'Coach, what am I doing wrong? What can I do better? Do you want me to play defense? What can I do to help us win?'"

Ivory injured his knee and wound up playing only four games. He was cleared to return late in the year, but Walkosky, not wanting to jeopardize Ivory's pro prospects by throwing him into a hopeless situation, wouldn't let him play.

Between Tiffin and Washington State, Ivory finished his college career with 130 rushing attempts -- hardly a résumé that excites NFL teams. He created a minor buzz at his pro day by running the 40 in 4.48 at 228 pounds, but he still was regarded as an unknown with baggage.

"That upset me so much," Walkosky said of the character questions. "He's a good kid. He just doesn't talk much. That doesn't make him a bad kid."

Once again, one person recognized his talent. This time, it was Saints Midwest scout Dwaune Jones.

So Ivory went to New Orleans, signed as an undrafted free agent.

In just the fourth game of his career, Ivory rushed for 158 yards against the Bucs in October 2010. AP Photo/Chris O'Meara

He was a revelation, leading the Saints in rushing as a rookie -- 716 yards and a 5.2 yards-per-carry average. His star burned out quickly, though, as injuries mounted in 2011 and 2012. He was buried on a crowded depth chart that included Mark Ingram and Darren Sproles. The Saints gave up on Ivory and traded him to the Jets for a fourth-round pick during the 2013 draft.

Once again, he was unable to finish.

"I don't know why they traded him," said a longtime personnel executive, speaking on condition of anonymity. "To me, he was the best back they had."

Splitting carries with Bilal Powell (2013) and Chris Johnson (2014), Ivory was solid in his first two seasons with the Jets. Mindful of his durability issues, the previous coaching staff limited his touches. The new staff, surprised by his speed, made him "the bell cow," as Jets coach Todd Bowles likes to say.

Shipp has worked with Ivory on trying to improve his patience, waiting for holes to develop before pressing the line of scrimmage. It's hard to keep a tiger in the cage when the door opens, but he's learning to set up blocks before attacking. He enjoys inflicting punishment, not absorbing it.

"He's always been effective, in my opinion, and it's going well and they keep feeding him," said New England Patriots coach Bill Belichick, whose defense will face Ivory on Sunday at Gillette Stadium. "I'd say he's a guy who gets stronger as the game goes on. ... He's hard to tackle in the first quarter. He's hard to tackle in the fourth quarter."

Ivory dominated his last two opponents, the Miami Dolphins and Washington Redskins, rushing for 312 combined yards to bring his total to 460 -- third in the NFL. He's more than halfway to his career high (833), and let's not forget that he missed a game due to a quadriceps injury.

The Jets are 4-0 with Ivory, 0-1 without him.

"I wouldn't trade him for anybody in this league," Shipp said.

After a decade of detours, Ivory is back to being the kid on the neighborhood field. This time, he's making fans scream like sirens.

"I'm tickled to death," said King, his high school coach. "I know what he's been through, people second-guessing his ability to play at this level. He's proving everybody wrong."